leaf-fall

leaf-fall (uncountable)

1. Alternative form of leaffall.
   • 2021 November 17, Philip Haigh, “Finding answers to low adhesion remains a high priority”, in RAIL, number 944, page 50:

     The report summary said: "The investigation found that there was contamination of the railhead in the area caused by leaf-fall and atmospheric conditions. [...]."

   • 2025 November 12, “Transport for Wales '153s' back in action”, in RAIL, number 1048, page 12:

     Transport for Wales has revived a number of its stored Class 153 units to provide extra cover during the autumn, when leaf fall on the rails can cause problems such as wheelflats for trains.

In practice, the form "leaf fall", without hyphen, seems to be more common. For example, the phrase "the leaf fall season" is less likely to be written as "the leaf-fall season".

• “leaf-fall”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.